Devolatilization of black shales from the Paraná Basin by magmatic interaction: an experimental approach

Abstract

It is widely thought that major volcanic events can play a key role in triggering biotic crises by introducing climate change volatiles, such as carbon dioxide and sulfur, into the atmosphere. Indeed, several mass extinction events coincide with the emplacement of large igneous provinces (LIPs), but not all LIPs are correlated with an extinction. It has been suggested that LIPs with higher sulfur (S) contents and with CO2- and sulfate-bearing bedrocks are more likely to trigger extinctions. The hypothesis has not been fully tested due to uncertainties in reconstructing original magmatic volatile contents and the volatile budgets of the sediments thermally affected by such magmas. Here, we propose to reconstruct original (undegassed) volatile contents of sediments via experimental methods (high T experiments in capsules loaded with sedimentary samples from Paraná-Etendeka). In that way, we intend to answer a longstanding question "Are bedrock sediments the key element defining the potential of LIPs to promote mass extinctions?"